— 177 — 



When the diketone Ci 2 H 2 o0 2 was oxidised with nitric acid or with 

 *an alkaline bromine solution it yielded dimethyl succinic acid and caryo- 

 phyllenic acid. When oxidised with permanganate of potassium the diketo 

 aldehyde was converted into the diketo acid C14H22O4 mentioned above. 

 Oxidation with nitric acid, as was to be expected, yielded caryophyllenic 

 acid and succinic acid. 



It follows from the investigations summarised above that the active 

 caryophyllenes are not, as was thought by Deussen, derivatives of naphtha- 

 lene, but of the terpenes or of systems allied to the latter. 



In conclusion the authors report that they have converted caryo- 

 phyllene prepared according to Deussen's method into its dihydrochloride 

 (m. p. 68 to 69°), and that this product proved to be identical with the 

 dihydrochloride from natural caryophyllene. 



Reduction of the blue caryophyllene nitrosite with sodium and alcohol af- 

 forded a body C15H27N (b. p. 148 to 150° at 13 mm.), which is probably an amine. 



On the formation of hydrocarbons from hydrazine compounds, see p. 195. 



Alcohols. 



Dihydrolinalool. In our last Report (p. 131) we described the alcohol 

 dihydrolinalool, which was formed in hydrating dihydromyrcene. For pur- 

 poses of comparison we had also prepared the alcohol synthetically from 

 methylheptenone and magnesium ethyl iodide. The methylheptenone had 

 been obtained both from citral (by oxidation), and from lemongrass oil 

 (by treatment with bisulphite-solution). In view of the fact that, contrary 

 to the experience with the product prepared from dihydromyrcene, we had 

 obtained no phenylurethane with sharp m. p. from this dihydrolinalool, we 

 also treated with magnesium ethyl iodide a methylheptenone which had 

 been prepared by boiling citral with aqueous solution of carbonate of po- 

 tassium according to Verley 1 ). But the dihydrolinalool prepared by this 

 method likewise failed to yield a phenylurethane with a sharp m. p. Its con- 

 stants, together with those of the products referred to above, are given 

 in the subjoined table: — 



Dihydrolinalool from 



B.p. 



diso 



nDiso 



Mol. 

 Found 



Refr. 

 Calc. 



Dihydromyrcene J 



92 to 92,5o 

 (12 to 13 mm.) 



0,8570 



1,45531 



49,47 



49,438 



Methylheptenone from citral (by oxidation) \ 

 %, p. 172,5 to 174°; d i5 o 0,8578) j 



77 to 78° (7 mm.) 



0,8588 



1,45641 



49,46 



49,438 



Methylheptenone from lemongrass oil ) 

 (B.p. 173 to 174°; d i5 ° 0,8550; n D20 ° 1,43965) J 



66 to 66,5° 

 (4 mm.) 



0,8575 



1,45661 



49,558 



49,438 



Methylheptenone from citral (by boiling \ 

 with solution of carbonate of potassium [ 

 [B.p. 66° (15 mm.); di 5 ° 0,8560; n D2 o° 1,44025] ) 



67,5° (4 mm.) 



0,8590 



1,45611 



49,424 



49,438 



M Bull. Soc. chim. III. 7 (1897), 175. 



12 



